CVE-2021-47592— net: stmmac: fix tc flower deletion for VLAN priority Rx steering
Quick assessment
Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于NULL指针取消引用。
Possible ATT&CK Techniques 3 AI
T1068 · Exploitation for Privilege Escalation T1203 · Exploitation for Client Execution T1055 · Process InjectionAffected Version Matrix 6
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| Linux | Linux | 0e039f5cf86ce2fcb62077a163e7ff3d7b7b7cf3< 97cb5c82aa1dd85a39b1bd021c8b5f18af623779 |
affected |
0e039f5cf86ce2fcb62077a163e7ff3d7b7b7cf3< aeb7c75cb77478fdbf821628e9c95c4baa9adc63 |
affected | ||
5.13 |
affected | ||
< 5.13 |
unaffected | ||
5.15.11≤ 5.15.* |
unaffected | ||
5.16≤ * |
unaffected |
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I. Basic Information for CVE-2021-47592
Vulnerability Information
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Vulnerability Title
net: stmmac: fix tc flower deletion for VLAN priority Rx steering
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: fix tc flower deletion for VLAN priority Rx steering
To replicate the issue:-
1) Add 1 flower filter for VLAN Priority based frame steering:-
$ IFDEVNAME=eth0
$ tc qdisc add dev $IFDEVNAME ingress
$ tc qdisc add dev $IFDEVNAME root mqprio num_tc 8 \
map 0 1 2 3 4 5 6 7 0 0 0 0 0 0 0 0 \
queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
$ tc filter add dev $IFDEVNAME parent ffff: protocol 802.1Q \
flower vlan_prio 0 hw_tc 0
2) Get the 'pref' id
$ tc filter show dev $IFDEVNAME ingress
3) Delete a specific tc flower record (say pref 49151)
$ tc filter del dev $IFDEVNAME parent ffff: pref 49151
From dmesg, we will observe kernel NULL pointer ooops
[ 197.170464] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 197.171367] #PF: supervisor read access in kernel mode
[ 197.171367] #PF: error_code(0x0000) - not-present page
[ 197.171367] PGD 0 P4D 0
[ 197.171367] Oops: 0000 [#1] PREEMPT SMP NOPTI
<snip>
[ 197.171367] RIP: 0010:tc_setup_cls+0x20b/0x4a0 [stmmac]
<snip>
[ 197.171367] Call Trace:
[ 197.171367] <TASK>
[ 197.171367] ? __stmmac_disable_all_queues+0xa8/0xe0 [stmmac]
[ 197.171367] stmmac_setup_tc_block_cb+0x70/0x110 [stmmac]
[ 197.171367] tc_setup_cb_destroy+0xb3/0x180
[ 197.171367] fl_hw_destroy_filter+0x94/0xc0 [cls_flower]
The above issue is due to previous incorrect implementation of
tc_del_vlan_flow(), shown below, that uses flow_cls_offload_flow_rule()
to get struct flow_rule *rule which is no longer valid for tc filter
delete operation.
struct flow_rule *rule = flow_cls_offload_flow_rule(cls);
struct flow_dissector *dissector = rule->match.dissector;
So, to ensure tc_del_vlan_flow() deletes the right VLAN cls record for
earlier configured RX queue (configured by hw_tc) in tc_add_vlan_flow(),
this patch introduces stmmac_rfs_entry as driver-side flow_cls_offload
record for 'RX frame steering' tc flower, currently used for VLAN
priority. The implementation has taken consideration for future extension
to include other type RX frame steering such as EtherType based.
v2:
- Clean up overly extensive backtrace and rewrite git message to better
explain the kernel NULL pointer issue.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于NULL指针取消引用。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2021-47592
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|---|
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Other References for CVE-2021-47592 (2)
Same Patch Batch · Linux · 2024-06-19 · 122 CVEs total
| CVE-2024-38558 | 10.0 CRITICAL | net: openvswitch: fix overwriting ct original tuple for ICMPv6 |
| CVE-2024-38570 | 9.8 CRITICAL | gfs2: Fix potential glock use-after-free on unmount |
| CVE-2021-47587 | 9.8 CRITICAL | net: systemport: Add global locking for descriptor lifecycle |
| CVE-2024-38544 | 9.8 CRITICAL | RDMA/rxe: Fix seg fault in rxe_comp_queue_pkt |
| CVE-2021-47611 | 8.1 HIGH | mac80211: validate extended element ID is present |
| CVE-2024-38587 | 7.8 HIGH | speakup: Fix sizeof() vs ARRAY_SIZE() bug |
| CVE-2024-38556 | 7.8 HIGH | net/mlx5: Add a timeout to acquire the command queue semaphore |
| CVE-2024-38610 | 7.8 HIGH | drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map() |
| CVE-2024-38605 | 7.8 HIGH | ALSA: core: Fix NULL module pointer assignment at card init |
| CVE-2024-38599 | 7.8 HIGH | jffs2: prevent xattr node from overflowing the eraseblock |
| CVE-2024-38592 | 7.8 HIGH | drm/mediatek: Init `ddp_comp` with devm_kcalloc() |
| CVE-2024-38564 | 7.8 HIGH | bpf: Add BPF_PROG_TYPE_CGROUP_SKB attach type enforcement in BPF_LINK_CREATE |
| CVE-2024-38568 | 7.8 HIGH | drivers/perf: hisi: hns3: Fix out-of-bound access when valid event group |
| CVE-2024-38572 | 7.8 HIGH | wifi: ath12k: fix out-of-bound access of qmi_invoke_handler() |
| CVE-2024-38578 | 7.8 HIGH | ecryptfs: Fix buffer size for tag 66 packet |
| CVE-2024-38580 | 7.8 HIGH | epoll: be better about file lifetimes |
| CVE-2024-38569 | 7.8 HIGH | drivers/perf: hisi_pcie: Fix out-of-bound access when valid event group |
| CVE-2024-38583 | 7.8 HIGH | nilfs2: fix use-after-free of timer for log writer thread |
| CVE-2024-38614 | 7.8 HIGH | openrisc: traps: Don't send signals to kernel mode threads |
| CVE-2024-38588 | 7.8 HIGH | ftrace: Fix possible use-after-free issue in ftrace_location() |
Showing top 20 of 122 CVEs. View all on vendor page → →
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V. Comments for CVE-2021-47592
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